1. Field of the Invention
This invention relates to the treatment of hydrocarbons and other compositions to remove sulfides therefrom. Compositions and methods are disclosed for the treatment of newly recovered crude oil, natural gas and the like to ameliorate the odors and other problems caused by the presence of sulfides such as hydrogen sulfide. The compositions can also be used to treat sulfides in sewage, pulp and paper manufacturing systems, and similar industrial fluids and suspensions.
2. Description of the Related Art
Various compositions have been proposed and used for the treatment of hydrocarbons to remove or otherwise treat hydrogen sulfide and/or other sulfides present in them. See, for example, Gatlin's U.S. Pat. Nos. 5,128,049, 5,486,605, 5,488,103, and 5,498,707, U.S. Pat. No. 4,978,512 in the name of Dillon, and Stanchem's Canadian Patent 2,269,476.
The treating agents for the removal of sulfides are often referred to as scavengers in the patent literature. Frequently the compositions are reaction products of aldehydes and amine compounds, and may or may not contain one or more triazines or derivatives thereof. See the descriptions in columns 5-8 of Trauffler et al. U.S. Pat. No. 5,698,171, Sullivan III et al. U.S. Pat. Nos. 5,674,377, 5,674,377 and 5,744,024, Rivers et al. U.S. Pat. No. 5,554,591, Weers et al. U.S. Pat. Nos. 5,074,991, 5,169,411, 5,223,127, 5,266,185, 6,024,866 and 5,284,576, Pounds et al. U.S. Pat. Nos. 5,462,721 and 5,688,478, Bhatia et al. Canadian patents 2,125,513 and 2,148,849, and Callaway U.S. Pat. No. 5,958,352. They may be contacted with the hydrocarbons in various ways as mentioned in these patents and others such as Galloway U.S. Pat. No. 5,405,591 and Fisher U.S. Pat. No. 6,136,282. Note that Callaway's ('352) trimer has the structure:

Sexton's GB patent 2,245,588 (p. 14) suggests the use of a reaction product of dimethylaminopropylamine and paraformaldehyde to treat fuel oils to prevent color and sediment formation. See also the triazines said to be useful for removing H2S in petroleum liquid, in Bhatia's U.S. Pat. No. 5,354,453. All of the patents identified in this paragraph and the preceding one are incorporated entirely by reference, as my invention may include the use of any of the sulfide scavengers recited or identified in them, particularly those containing at least one nitrogen, as a complement to the invention described herein.
The above cited references do not utilize the triazine compound described below to remove sulfides from hydrocarbons.
Many of the scavengers mentioned in the above cited patents remain, in one form or another, in the hydrocarbons they are used to treat. That is, they may be effective at suppressing the evolution of hydrogen sulfide, for example, but the sulfur is left in the hydrocarbon. There is a need for a method of treating hydrocarbons which does not merely neutralize the sulfur compounds, but enables the ready removal of them from the hydrocarbons.